I COMPLETELY agree with rear speakers being for rear-fill. I completely DISAGREE with running some speakers off of a head unit and some off of an amplifier - all of which are playing the same frequencies.

My agenda is the ultimate in sound quality. Unlike others on this board, I have a resume to back up actually understanding SQ and what it takes to achieve it.

If you want the honest truth, in most vehicles that desire depth in their sound system, and a very realistic and wide sound stage, I usually don't do ANY rear speakers. The last thing you want to do is have rear speakers that are going to sound different than the fronts, especially if you are going for rear-fill.

Amplifying rear speakers has nothing to do with SPL, as only the subs really dictate your bass output. Onyx's 14 years of doing this should have helped him understand what I was trying to say.....but then again I see people everyday in this industry that have done it 20+ years, and have done it wrong for 20+ years.

If you want to know business, do you listen to your high school economics teacher who has been teaching 20 years, or Donald Trump? Reputations speak for themselves.